1. Field of the Invention
Finishing machines or apparatus, centrifugal finishing apparatus which embodies means for exit of finishing media and finished parts and for separation thereof, such apparatus which is self-separating and which embodies automatic media return.
2. Prior Art
Centrifugal finishing devices have become increasingly popular during recent years because of their rapid finishing action, but efficient separation means or procedure has not previously been available for employment in or together with such centrifugal finishing devices. Accordingly, although finishing with such centrifugal finishing apparatus has to date been rapid, efficient, and relatively economical, such advantages have been lost due to the inability to provide or even conceive a suitable and satisfactorily economical separation procedure and apparatus therefor, especially one which eliminates or involves a minimum of manual labor. Moreover, it has been found that centrifugal finishing apparatus, as presently conceived and available, has definite and serious size limitations. The usual type of centrifugal apparatus cannot be extended beyond certain maximum size limits without serious disadvantages. For example, it has been found in these laboratories that, when the diameter of the spinner member in the centrifugal finishing apparatus exceeds a certain maximum, excessive variations in tolerances between the circumference of such spinner member and the complementary opening in which it is adapted to rotate occur, resulting in inadequate seals, excessive leakage of fluid and solid materials at the juncture between the periphery of the spinner member and the edge of the opening in which it is adapted to rotate, and considerable mechanical and other difficulties, including excessive down time and maintenance, then result. These shortcomings cannot be cured by improving the nature of the seal between the rotating and the stationary member, inasmuch as seals have a maximum sealing capacity and the fluctuations and variations encountered with oversized centrifugal finishing apparatus have to date eliminated any practical or economic applications requiring relatively large finishing volume or capacity, and the attendant machine size which would be most economical for such applications. Therefore, at the present time the application of centrifugal finishing apparatus has not reached its full potential due to shortcomings in separation procedure and apparatus for use in combination therewith, as well as inherent size limitations or restrictions found to exist with centrifugal finishing apparatus as its has been conceived up until the present date. It is apparent that improved centrifugal finishing apparatus and procedure, which is not characterized by the inherent shortcomings, deficiencies, and inabilities of the prior art centrifugal finishing apparatus and system, would be highly desirable and would fill a long-felt need in the art. Such apparatus is provided by the present invention, which eliminates the inherent shortcomings and deficiences of prior art centrifugal finishing apparatus and systems while retaining the most desirable characteristics and advantages thereof and adding additional advantages thereto.
As representative of prior art in this area of the surface-finishing field may be mentioned U.S. Pat. Nos. 3,435,567; 3,990,188; 4,026,075; 4,177,608; and RE 29,964.